(1)
Sources in brackets after each entry start with + OR
H for HMSO, followed by main sources in approximate
publication date order e.g J for Jane's, C for Conway's
etc. All other sources, which are in lower case, follow in
alphabetical order.

(2)
It is realised that some publications will have used the same
primary sources for their information, but there are
enough variations to warrant noting those that agree and
disagree. This might help to highlight data about which
there are doubts.

(3)
Within a given area e.g. North Sea, ships attacked
are generally listed in order North to South, and West to
East; the exception is the English Channel which goes East
to West, or down-Channel.

(4) Ships in BOLD capitals are those sunk or
otherwise lost; in lower case bold, attacked
and/or damaged. Variations in the published information
are in brackets starting with an abbreviation for the
source e.g. (wi
- in 53.50N, 00.50E).

(5)
Loss, attack and damage dates are normally
those given in the original HSMO publication. Corrections,
often the result of later and more accurate research, are
included in the entry in bold.

(6)
Time of attack and time of sinking appear
to be used interchangeably in most sources. Unless the
vessel exploded or sank almost instantly (for example, an
ammunition or iron ore ship), there would be a delay of
from minutes to hours or even days between damage
inflicted and ship disappearing beneath the water or being
beached. Where possible, these differences are identified.

(7)
Times of sinking may be British or German depending
on the source - there is usually a 1 hour difference

(8)
All identified loss positions are quoted, whether
bearings or latitude and longitude. Variations may be due
to a number of reasons including incorrect transcription.
No attempt has been made to reconcile the differences.

(9)
Where two U-boat attack positions are quoted,
mainly by U-boat.net, both are quoted without comment.

(11)
Auxiliary and hired vessel information
is in the order - gross tonnage/build year, owner,
registration port or place of ownership/ management, crew
if known, master or skipper, voyage and cargo, conditions
if known. How sunk or damaged, lives lost (source
abbreviations starting with + for original HMSO)

Merchant
Vessels

(12)
Merchant ship and fishing vessel information is generally in the order - gross tonnage/build year, owner,
registration port or place of ownership/management, crew
if known, master or skipper, voyage and cargo, conditions
if known. How sunk or damaged, lives lost (source
abbreviations starting with + for original HMSO)

(13)
Three items of information, the first two from the
original HMSO lists, have been excluded to save
space. (i) All merchant ships and
fishing vessels torpedoed, were ATTACKED WITHOUT
WARNING; (ii) if no casualties are shown, NO LIVES
WERE LOST; (iii) all sinkings and attacks were by GERMAN
SUBMARINES or U-boats unless otherwise stated.

(14)
All merchant ships are steamships, unless
otherwise identified, and mainly cargo ships - "cargo
steamship" is sometimes added as a reminder. Where known,
liners, passenger & cargo ships, and colliers are
identified, plus tankers, tugs, dredgers etc. Those
carrying coal may be colliers but this is not assumed.

(15)
Merchant ships have their gross registered tonnage
(grt) first and then year of build. Even small differences
in grt are usually noted. Searching the internet for ships
whose names are in common use e.g. SS New York City, can
be helped by adding the correct grt in the search box.

(16)
Some colliers sunk and damaged may have been
Admiralty-chartered, but unless specifically listed as
such, are included with the merchant ships.

(17)
Merchant vessel ownership is often a total puzzle,
and little attempt has been made to sort them out.
Instead, variations are usually noted without comment, and
even these may be wrong or misleading or just out-of-date
due to change of ownership. The companies named may
include holding companies, subsidiaries, charterers,
managers, etc., and the place names can be ports of
registration or locations of offices.